A fermentation technique used in France, in which a macération carbonique (carbonic acid maceration) is started with part of the grapes (usually about half). Then a normal alcoholic fermentation is started by adding conventionally destemmed, macerated grapes. The resulting fermentation carbon dioxide then displaces the oxygen upwards. In the past, this is probably how most red wines were made. The whole grapes - without destemming - are put into a fermentation tank in several tranches. The weight of the grape must then causes spontaneous fermentation in the intact berries, and the carbon dioxide that escapes produces the effect that is usual with macération carbonique.